The current research experimentally studied flame speed and stretch under engine in-cylinder conditions. A direct-injection, spark-ignition, and optically accessible engine was utilized to image the flame propagation, and E10 was selected as the fuel. Also, three fuel–air mixtures (stoichiometric, lean, and rich) were examined. The flame front was located by processing high-speed images. This study introduces a novel approach for calculation of equivalent spherical flame radius for analysis of flame speed and stretch. Flame front propagation analysis showed that during the flame propagation period, the stretch decreased until the flame front touched the piston surface. This was a common trend for stoichiometric, lean, and rich mixtures, which occurred because the flame radius was the dominant factor in the stretch calculation. In addition, the rich fuel–air mixture showed a lower flame stretch compared to stoichiometric or lean mixture. This was the result of a lower Markstein number for the rich fuel–air mixture. To study the sensitivity of different fuel–air mixtures to the flame stretch, the trajectory of the flame centroid was tracked until the flame front touched the piston surface. The results showed that the end centroid for the lean mixture deviated from the start point more than those of the rich and stoichiometric mixtures because the lean mixture had a higher flame stretch and lower flame speed. Furthermore, comparing the flame stretch at three different engine speeds revealed that increasing the engine speed increased the flame stretch, especially during the early flame development period. According to previous studies which discussed flame stretch as a flame extinguishment mechanism, the probability of flame extinction is higher when the engine speed is higher. Also, uncertainty analysis was conducted to determine the effect of camera setting on the flame stretch. Results showed that a maximum relative uncertainty of 4.5% occurred during the early flame development.
ContiJHoltbergPDiefenderferJLaRoseATurnureJTWestfallL. International energy outlook 2016 with projections to 2040. Washington, DC: U.S. Department of Energy, Energy Information Administration, Office of Energy Analysis, 2016.
2.
SongMZengLChenZLiZZhuQKuangM. Industrial application of an improved multiple injection and multiple staging combustion technology in a 600 MWe supercritical down-fired boiler. Environ Sci Technol2016; 50(3): 1604–1610.
3.
BonefačićIWolfIBlecichP. Improvement of fuel oil spray combustion inside a 7 MW industrial furnace: a numerical study. Appl Therm Eng2017; 110: 795–804.
AfkhamiBKakaeeAHPouyanK. Studying engine cold start characteristics at low temperatures for CNG and HCNG by investigating low-temperature oxidation. Energ Convers Manage2012; 64: 122–128.
6.
BoldajiMRSofianopoulosAMamalisSLawlerB. CFD simulations of the effect of water injection characteristics on TSCI: a new, load-flexible, advanced combustion concept. In: ASME 2017 internal combustion engine division fall technical conference, Seattle, WA, 15–18 October 2017, paper no. V001T03A019. New York: American Society of Mechanical Engineers.
7.
JamaliANalimMR. Numerical simulation of dual-fuel compression-ignition engine in part-load operating condition with double injection. In: ASME 2016 internal combustion engine division fall technical conference, Greenville, SC, 9–12 October 2016, paper no. V001T06A011. New York: American Society of Mechanical Engineers.
8.
JohnsonDRHeltzelRNixACClarkNDarziM. Greenhouse gas emissions and fuel efficiency of in-use high horsepower diesel, dual fuel, and natural gas engines for unconventional well development. Appl Energ2017; 206: 739–750.
9.
PetersN. Turbulent combustion. Cambridge: Cambridge University Press, 2000.
10.
FoglaNCretaFMatalonM. Effect of folds and pockets on the topology and propagation of premixed turbulent flames. Combust Flame2015; 162(7): 2758–2777.
11.
BrequignyPHalterFMounaïm-RousselleCDuboisT. Fuel performances in Spark-Ignition (SI) engines: impact of flame stretch. Combust Flame2016; 166: 98–112.
12.
KarlovitzBDennistonDWKnapschaeferDHWellsFE. Fourth symposium (international) on combustion. Baltimore, MD: Williams and Wilkins, 1953, pp.613–619.
13.
DamköhlerG. Der einfluss der turbulenz auf die flammengeschwindigkeit in gasgemischen. Zeitschrift für Elektrochemie und angewandte physikalische Chemie1940; 46(11): 601–626.
14.
BorghiR. On the structure and morphology of turbulent premixed flames. In: CasciCBrunoC. (eds) Recent advances in the aerospace sciences. Boston, MA: Springer, 1985, pp.117–138.
15.
Von ElbeGLewisB. Combustion, flames, and explosions of gases. New York: Academic Press, 1961.
MatalonM. On flame stretch. Combust Sci Technol1983; 31(3–4): 169–81.
18.
BuckmasterJ. The quenching of two-dimensional premixed flames. Acta Astronaut1979; 6(5–6): 741–769.
19.
IshizukaSLawCK. An experimental study on extinction and stability of stretched premixed flames. Sym (Int) Combust1982; 19(1): 327–335.
20.
JuYMatsumiHTakitaKMasuyaG. Combined effects of radiation, flame curvature, and stretch on the extinction and bifurcations of cylindrical CH4/air premixed flame. Combust Flame1999; 116(4): 580–592.
21.
GiannakopoulosGKGatzoulisAFrouzakisCEMatalonMTomboulidesAG. Consistent definitions of “flame displacement speed” and “Markstein length” for premixed flame propagation. Combust Flame2015; 162(4): 1249–1264.
22.
DeshaiesBCambrayP. The velocity of a premixed flame as a function of the flame stretch: an experimental study. Combust Flame1990; 82(3–4): 361–375.
23.
WuFSahaAChaudhuriSLawCK. Propagation speeds of expanding turbulent flames of C4 to C8n-alkanes at elevated pressures: experimental determination, fuel similarity, and stretch-affected local extinction. P Combust Inst2015; 35(2): 1501–1508.
24.
BechtoldJKMatalonM. The dependence of the Markstein length on stoichiometry. Combust Flame2001; 127(1–2): 1906–1913.
25.
GuXJHaqMZLawesMWoolleyR. Laminar burning velocity and Markstein lengths of methane–air mixtures. Combust Flame2000; 121(1–2): 41–58.
26.
GöttgensJMaussFPetersN. Analytic approximations of burning velocities and flame thicknesses of lean hydrogen, methane, ethylene, ethane, acetylene, and propane flames. Sym (Int) Combust1992; 24(1): 129–135.
27.
BradleyDHicksRALawesMSheppardCGWoolleyR. The measurement of laminar burning velocities and Markstein numbers for iso-octane–air and iso-octane–n-heptane–air mixtures at elevated temperatures and pressures in an explosion bomb. Combust Flame1998; 115(1–2): 126–144.
28.
LiuYCSavasAJAvedisianCT. Comparison of the burning characteristics of indolene and commercial grade gasoline droplets without convection. Energ Fuel2012; 26(9): 5740–5749.
29.
MetghalchiMKeckJC. Burning velocities of mixtures of air with methanol, isooctane, and indolene at high pressure and temperature. Combust Flame1982; 48: 191–210.
30.
BayaniSTabeYKangYTLeeSHChoiCK. Surface plasmon resonance imaging of drop coalescence at high-temporal resolution. J Flow Vis Image Process2018; 25(3–4): 191–205.
31.
RatzkeASchöfflerTKuppaKDinkelackerF. Validation of turbulent flame speed models for methane–air-mixtures at high pressure gas engine conditions. Combust Flame2015; 162(7): 2778–2787.
32.
SalazarVKaiserS. Influence of the flow field on flame propagation in a hydrogen-fueled internal combustion engine. SAE Int J Engines2011; 4(2): 2376–2394.
33.
GoschützMSchulzCKaiserSA. Endoscopic imaging of early flame propagation in a near-production engine. SAE Int J Engines2014; 7(1): 351–365.
34.
Abdi AghdamE. Improvement and validation of a thermodynamic SI engine simulation code. PhD Thesis, University of Leeds, Leeds, 2003.
35.
AleiferisPGSerras-PereiraJRichardsonD. Characterisation of flame development with ethanol, butanol, iso-octane, gasoline and methane in a direct-injection spark-ignition engine. Fuel2013; 109: 256–278.
36.
VeynanteDLodatoGDomingoPVervischLHawkesER. Estimation of three-dimensional flame surface densities from planar images in turbulent premixed combustion. Exp Fluids2010; 49(1): 267–278.
37.
ZhangMWangJJinWHuangZKobayashiHMaL. Estimation of 3D flame surface density and global fuel consumption rate from 2D PLIF images of turbulent premixed flame. Combust Flame2015; 162(5): 2087–2097.
38.
ChaudhuriSSahaALawCK. On flame–turbulence interaction in constant-pressure expanding flames. P Combust Inst2015; 35(2): 1331–1339.
39.
AleiferisPGMalcolmJSToddARCairnsAHoffmannH. An optical study of spray development and combustion of ethanol, iso-octane and gasoline blends in a DISI engine. SAE technical paper 2008-01-0073, 2008.
40.
BradleyDGaskellPHGuXJ. Burning velocities, Markstein lengths, and flame quenching for spherical methane-air flames: a computational study. Combust Flame1996; 104(1–2): 176–198.
41.
KoupaieMMCairnsALanzanovaT.Cyclically resolved flame and flow imaging in an SI engine operating with future ethanol fuels. SAE technical paper 2017-01-0655, 2017.
42.
SuzukiKUeharaKMuraseENogawaS. Study of ignitability in strong flow field. In: GüntherMSensM. (eds) International conference on ignition systems for gasoline engines. Cham: Springer, 2016, pp.69–84.
43.
BrequignyPMounaïm-RousselleCHalterFMoreauBDuboisT. Impact of fuel properties and flame stretch on the turbulent flame speed in spark-ignition engines. SAE technical paper 2013-24-0054, 2013.
44.
RimmerJELongEJGarnerCPHargraveGKRichardsonDWallaceS. The influence of single and multiple injection strategies on in-cylinder flow and combustion within a DISI engine. SAE technical paper 2009-01-0660, 2009.
45.
DavyMHWilliamsPAAndersonRW. Effects of fuel composition on mixture formation in a firing direct-injection spark-ignition (DISI) engine: an experimental study using Mie-scattering and planar laser-induced fluorescence (PLIF) techniques. SAE technical paper 2000-01-1904, 2000.
46.
RottenkolberGGindeleJRaposoJDullenkopfKHentschelWWittigS, et al. Spray analysis of a gasoline direct injector by means of two-phase PIV. Exp Fluids2002; 32(6): 710–721.
47.
DahmsRNDrakeMCFanslerTDKuoTWPetersN. Understanding ignition processes in spray-guided gasoline engines using high-speed imaging and the extended spark-ignition model SparkCIMM. Part A: spark channel processes and the turbulent flame front propagation. Combust Flame2011; 158(11): 2229–2244.
48.
DahmsRNDrakeMCFanslerTDKuoTWPetersN. Understanding ignition processes in spray-guided gasoline engines using high-speed imaging and the extended spark-ignition model SparkCIMM. Part B: importance of molecular fuel properties in early flame front propagation. Combust Flame2011; 158(11): 2245–2260.
49.
WangYZhangJYangZWangXDicePShahbakhtiM, et al. Investigation of flow conditions and tumble near the spark plug in a DI optical engine at ignition. SAE technical paper 2018-01-0208, 2018.
50.
DecJEYangYDronniouN. Improving efficiency and using E10 for higher loads in boosted HCCI engines. SAE Int J Engines2012; 5(3): 1009–1032.
51.
DemesoukasSBrequignyPCaillolCHalterFMounaïm-RousselleC. 0D modeling aspects of flame stretch in spark ignition engines and comparison with experimental results. Appl Energ2016; 179: 401–412.
